1. Field of the Invention
The present invention relates generally to flow measurement techniques. More particularly, the present invention provides a MEMS chip for wind speed measurements.
2. Description of the Related Art
Wind speed is a fundamental atmospheric rate and affects weather forecasting, aircraft and maritime operations, construction projects, growth and metabolism rate of many plant species, and countless other implications. Wind speed is measured using anemometer, which measures wind's speed or pressure. The wind pressure is calculated as:
      p    w    =            ρ      ⁢                          ⁢              V        2              2  And Bernoulli's equation states:pt=ps+pw Solving that for speed we get:
  V  =                    2        ⁢                  (                                    p              t                        -                          p              s                                )                    ρ      where:
V is the wind speed;
Pw is the wind pressure;
Pt is the stagnation pressure;
Ps is the static pressure;
ρ is the air density.
To date, microfabricated MEMS pressure sensor is widely used. However, to the best of my knowledge, MEMS pressure sensor has limited application in measuring the wind pressure.
Microelectromechanical systems (MEMS) (also written as micro-electro-mechanical, MicroElectroMechanical or microelectronic and microelectromechanical systems) is the technology of very small devices. MEMS pressure sensor usually consists of several components that interact with the pressure to be measured and some electrical components that process data. MEMS pressure sensor usually outperforms a pressure sensor made using the most precise macroscale level machining techniques. The benefits include high output sensibility, reliable batch production, good repeatability, low costs, low power, miniaturization, high performance, and integration etc. Anemometer based on MEMS chip is expected to carry on these benefits into the field and is highly desired.